Question

If each side of a cube is increased by 50%. Find the percentage increases in its surface area.

Answer 1

Increase by 50 % = a+a/2 = 3a/2
Surface Area of original cube = 6a² = 6x(3a/2)² = 13.5 a² 
Increase in area = (13.5 - 7)a² =7.5 a²
Increase % = 7.5 a²/6a² x 100 = 125%

Answer 2

Let the edge = a cm So increase by 50 % =  = Total surface Area of original cube = TSA of new cube = ==  Increase in area =  =  Increase % = = 125%